Fluid pressure accumulator



Jan. 25, 1944.

G. J. HUEBNER1R., ET A l. 2,340,125

FLUID PRESSURE ACCUMULATOR Filed Jan. 14,` 1942 stone: a. H'UE' E .san BYeoRnoN n. PENNIgga-(ron` E? //wwsffz am' ATTORNEYS use *rm-ferri" Y George r. einem, trainen-oie,

Gordon E.

x 1 rr tj-ifs. ration, i' The aco racno 3.5i, i342, Serial No. 425522 accumulator of this kind have to be thick enough l to serve this clamping action and to also aciiitate secure attachment o the sections to each other, it has been the practice to ini form ythe entire walls of sections to the thicmess required at their mating edge portions and to then turn down all but the mating edge portions to the' thickness dictated by the pressure under whichl :duid medium is to he accumulated. Considerable diihculty has also been encountered in clamping the .margins of the diaphragm between the mating edges of the forged sections withom injuring the diaphragm.

One of the main objects ofthe invention is to provide an accumulator having semi-spherical symmetrical sections adapted to he io from' sheet of substantially uniform thi.

Another object of the invention is the provision oi improved means for clamping together the mating edges of sheet metal sections of this md and simultaneously, hermetically sealing the edge Y portions oi an elastic diaphragm therebetween in orer to partition the interior of the la r.

Other objects of the invention are toprovide a diaphragm in a device of this kind which has a marginal portion formed to cooperate with the mating edges of the semi-spherical sheet metal sections in partitioning one compartment in the interior of the accumulator from another; to provide a metal wire reinforcing' ring in the A formed marginal edge portions of the diaphragm which is so located when the parts of the device are assembled as to lock the outer edges of the diaphragm against'movement in respectively opposite directions through the compression of thicknesses of the elastic diaphragm material between the ring and associated portions of the sheet metal wall structure; to provide rigid clamping members around the mating edges et the sheet metal sections which exert a. press tting engagement upon the latter; to provide a clamping member of this kind which has spacedv jaws so shaped with respect to the mating edge portions as to somewhat deform the. extremities of the latter about a rigid wire ring positioned therebetween.

additional objects of the invention are to pro' vide improved ttings for accommodating connecon o the iiuid pressure conduits to the chambers at respectively opposite sides ci the die; to provide ttings of this mnd which are adapted to he mounted on the sheet metal wall structure mainly by a press tting engagement on a. ange comprising outwardly heut por tions of the sheet metal wall portions surrounding an aperture therein: to provide an internal seal between the wall structure and tting which comprises yieldable material; and to provide a mrt member on an inclined portion oi the tting which extends into the interior of the accumu later for compressing the yleldable seal and bear ing outwardly against the internal surface ci the wall stmcture in opposition to an abutment on the tting which contacts corresponding parte of the external surface 'of the wall structure in order to clampingly assist in attachment of the tting to the latter.

an illustrative embodiment of the invention is shown in the accompanying drawing. in' which:

Fig. lois a side-elevational view of an accumulator embodying the invention,

Fig. 2 is a contrai sectional 'view taken on the line of M. l..

Fig. 3 is an enlarged fr sectional view of the structure wit-hin the circle A oi Fig. 2.

Fig. s is a fragmentary sectional view of the formed edge portions of the diaphragm illusv 35 trated in Hg. 3 but showing the latter muncompressed state.

Fig. 5 is an enlarged detail -view cf the fitting Yshown attherightihig.

The accumulator illustrated in the drawing may he used in any uid pressure system-hut it is particularly adapted' for use in fluid pressure systems of airplanes which are relied upon to operate accessory equipment such as mech for raising and lowering landing gears. The purpose ci the accumulator is to store iiuid under pressure during proper operation oi the engine of the airplane so as to provide reserve energy in the event operation of the engines is discontinued in order t`6 eiilciently operate the landing gear lifting and lowering apparatus and other uid pressure responsive mechanism with which the airplane is provided. l

The accumulator embodying our invention comprises substantially identical 'semi-'spherical sections IB which are formed in suitable dies from mating edge portions II y ring 22 is disposed. In assembling this structure.

sheet metal of substantially uniformy thickness. The edge portions of the sections I2 are bent outwardly to provide mating edges I I having Junctions I2 of arcuate cross section between the outer extremities thereof and the main body portions of the sections III'.

An elastic diaphragm I2 disposed in the interior of the accumulator is provided with formed marginal edge portions I4 which comprisel oppositely extending flanges Il and an intermediate outwardly extending web I2. 'I'he elastic diaphragm I2 preferably comprises rubber or synthetic rubber-like material such as Neoprene and the web I2 of its formed edge portions is 'adapted to extend between the arcuate Junctions and innermost parts of the mating edge portions II. The surfaces of the flanges I5 of the formed edge portions of the diaphragm are shaped to conform with the surface of the arcuate junctions I2 and adjacent parts of the mating edge and body portions II and III respectively. These surfaces, as illustrated in Fig. 4, are also provided with relatively sharp edged projecting ribs I1 which are adapted to be firmly compressed against the surfaces -of the sheet metal sections I2 with which they register when the diaphragm is clamped in position between the latter. The ribs I1 4serve to localize the pressure applied by the formed edges of the diaphragm upon the internal surface of the sheet metal sections I2 with which they contact thereby producing effective seals between n these parts ofthe structure.

'I'he formed edge portion I4 of the diaphragm I2 is provided at a location opposite the web I2 thereof with a circumferentially extending groove I2 in which I9. The wire ring is so located with respect-to the surfaces of the formed edge portions of the diaphragm which contact with'the 'arcuate'junction portions I2 of the Asheet metal sections I2 as to provide a relatively-'thin thickness of rubber between the wire arcuate Junction portions I2. This relatively thin thickness of rubber is stressed in compression 'in resisting displacement of the wire ring I9 and associated portion of the formed edge part of the diaphragm in respectively opposite directions. A wire ring 20 is disposed between the outer extremities of the mating edge portions I I of the sheet metal sections I0 inorder to positively hold the outermost parts of the mating edge portions against inward movement beyond a predetermined limit.

A clamping band numeral 2| portions of to securely the web IB is disposed around the mating edge the sheet metal sections I0 in order hold the latter together and to retain of the formed edge portions of the diaphragm under compression between parts of the mating edge portions.y The clamping band 2| comprises complementary rings 22 and 22 having spaced jaws 24 and 25, respectively, which are arcuately formed to bear against theexternal surfaces of'the arcuate junctionportions I2 of the sheet metal sections I0 as illustrated in Fig. 3. The jaws 24 and 25 are recessed as'at 28 to accommodate the outer extremities of the between which the wire the inner extremities of the jaws 24 and which is disposed a rigid wire ringl generally designated by the x diameter to provide a clearance II between it v cent the inner surfaces of the sheet metal section v ring |9 and the opposite I2 at which the opening 22 is located. The sealregister with the junction portions I2 of the mat.

ing edges actually deior'mthe sheet metal ofthe mating edge portions inwardly to iirmly clamp the vane I8 ofthe formed edges of the diaphragm I2 between the mating edge portions Il. The

v--inetal of the wall fluid medium of a fluid complementary rings 22 and 22 are firmly urged together by a series of bolts 21, the heads of alternate bolts of winch are disposed on respectively opposite sides of the clamping band 2| and threaded in apertures of correspondingly opposite rings of the clamping band. Formed in the complementary rings 22 and 22 are registering grooves 22'and 22, respectively. The metal between the grooves 22 and 22 of the rings and the grooves between the jaws 24 and 22 is cut away as illustrated at 22 so as to cause the rings '22- and 22 to abut only at' 2i. The unthreaded shank portion 52 of each bolt 21 is reduced in and the walls of the opening in the ring through which it extends. tion, the force applied on the rings 22 and 22 by the bolts 21 is transmitted by leverage of considerable length to the jaw portions 24 and 22 and from the latter to the mating edge portions of the sheet metal sections I2.

Each sheet metal section I2 is provided with an opening 22 which is surrounded by an outwardly bent ilange 22 comprising portions of the sheet structure. Mounted in each opening 22 is a ntting generally designated by the numeral 24 which is adapted to facilitate communicative connection of a conduit to the chamberon respectively opposite sides of the diaand a head portion 21 in which is formed a tapered groove 22. The tubular body part 22 ofthe fitting is adapted to extend into the interior of the accumulator while the flange 22 is receivable in a press-litted relationship in the tapered groove 2l. A sealing washer 22, preferably comprising rubber or synthetic rubber-like material tuch as Neoprene which is resistant to oil. is disposed around-the tubular body portion 22 adjaing member 22 is compressed against such sur-- races ofthe sheet metal section I2 by a nut member 42 threaded on the threads l22 of the exterior of the tubular bidy section 2l. The nut 421s pro- I the interior of the accumulator through the cenof the tubular body portion 25. The

tra! passage external end of the central passage of the fitting 24 shown at the right side of Fig. 2 is threaded to receive a valve member 44 by which air pressure may be applied on one side of the diaphragm I2. The fitting shown at the left side of Fig. 2 is.similar in construction to the'ntting shownat the right side thereof with the exception that an externally threaded nipple 4I is formed on the outer extremity of the fitting to accommodate the attachment thereto pressure system may be supplied to the opposite side of the diaphragm I2.

In operation, `the space on the right side of the diaphragm I2 is lined with air under pressure of a predetermined value. 'I'hen fluid medium is supplied under pressure of ahigher value through `By virtue of this construc' of a conduit 42 by which I the iitting of the left side of the accumulator.' thus further compressing the air on theright side of the diaphragm. The air pressure applied on l the right side of the diaphragm may be predetermined to establish the eiective pressure of the iiuid medium which is stored in the left side of the diaphragm as viewed in Fig. 2.

An accumulator embodying the invention can be conveniently inexpensively formed of sheet metal of uniform thickness without requiring exmulator and having-'a thickened vformed outer` edge portion comprising oppositely extending lateral flanges for seating upon the internal tion of the diaphragnimay be hermetically clampingly sealed between the mating edge por-l tions of the sheet metal sections with suillcient force to withstand pressures of the` order to. which devices of'this mnd are conventionally subjected. l Although but one speciiic embodiment of the invention is herein shown and described. it will be understood that various changes in the vshape and arrangement of parts may be made without departing from the spirit ofthe invention.

We claim:

l. A iluid pressure accumulatorcomprising complementary sheet steel sections having main wall portions and outwardly extending mating edge portions, a' diaphragm comprising resilient material for partitioning the interior'of said accumulator and having outer Iedge portions extending between parts of said mating edge portions, a metal wire disposed outwardly of said outer edge portions of the diaphragm between the remaining partsof said mating edge portions, and a clamping band surrounding said mating edge portions having opposed jaw portions bearing against the exterior of the latter at. a location between said metal wire and said main wall portions for compressing the outertween the remaining parts of said mating edgeportions, a metal wire embedded in said diaphragm inwardly of the internal surface of said sections and having portions registering with said first mentioned metal wire, and: aclamping band surrounding said mating edge portions having opposed jaw portions bearing against the exterior of the latter at a location between said metal wires for compressing the outer edge portions oi said diaphragm between parts of said mating edge portions and urging the remaining parts thereof against'sa'id metal wire.

3. A iuid pressure accumulator including complementary .substantially identical, semi-spherical sheet steel sections Ahaving spaced outwardly extending mating edge portions provided with approaching' extremities and forming 'therebetween an annular recess having a restricted extremity, a diaphragm comprising resilient material for partitioning the interior of said'accusurface of said sections adjacent said mating edge .portions and having an intermediate radially outwardly extending iiange protrudingl between said mating edge portions forming a seal therebetween, a wire ring disposed in the revstricted extremity of ysaid recess adjacent the outer edge of said radial flange, and aclamping vband surrounding said mating edge portions having opposed jaw portions bearing against the exterior of the latter at `a location inwardly of said wire ring for deiiecting said mating edge portions inwardly about said wire ring as a fulcrum in order to compress saidradial ange between said mating edge portions'and urging the approaching extremities of the latter against Y said wire ring. 1

4. A uid pressure accumulator including l semispherl'cal sheet steel sections having spaced outwardly extending mating edge portions provided with approaching extremities and Aforming therebetween an annular recess having a restricted extremity, a diaphragm comprising resilient material for partitioning the interior of said accumulator and having a thickened formed outer edge portion comprising oppositely extending lateral anges for seating upon the internal surface of said sections adjacent said 'mating edge portions and having an intermediate radially outwardly extending flange protruding betweenV said mating edge portions-forming a seal therebetween, a wire ring disposed in the restricted extremity of said recess beyond the outer edge oi said radial iiange, a clamping band surrounding said mating edge portions having opposed f jaw portions bearing `against the exterionof the plane as the latter for cooperating with said rst mentioned wire ring in conilning said radial Aflange against expansion in a direction normal to its thickness, said inner wire ring being spaced .from the junction of the wall of said accumulator and the mating edge portions thereof by only a small thickness oi said resilient material in order to hold said inner ring against substansurface of 4said sections adjacent said mating edge portions and having an intermediate ra'- dially outwardly extending ange conforming in shape with said tapered annular recess and .protruding between said mating edge A:portions forming a seal therebetween, said lateral 'ilanges having ridges on the surfaces thereof which en- -cal sheet metal sections and disposed between ring between said mating edges gage said internal surfaces for increasmg the sealing action between saiddiaphragm and said i wire ring.

6. A fluid pressure Vaccumulator including complementary substantially identical, semispherical sheet metal sections having spaced outwardly extending mating edge portions comprisin g arcuately bent portions of said sheet metal having substantially regular and continuous surfaces, a rubber diaphragm having a thickened formed periphery adjacent said bent edge portions, said formed peripheryliaving -opposite portions bearing against the exterior vature of said arcuately bent portions and seated v' thereon and provided with deformable seating ridges engageable with said continuous surfaces ofsaid bent edge portions for normally producing a` localized sealing pressure between said formed periphery and said surfaces, said formed periphery -of said diaphragm having a web portion extending outwardly radially between said mating edge portions. and a clamping ring having opposed jaw portions engaging the 'external surfaces of said arcuately bent portions for urging the same toward each other and clampingly compressing said' web therebetween. s

7. A fluid pressure accumulator including complementary substantially identical, semi-spherical sheet metal sections having spaced outwardly extending mating edge portions comprising arcuately bent portions of said sheet metal, a rubber diaphragm having a. thickened formed' pe.- riphery adjacent said bent edge portions, said formed periphery having opposite laterally extending iianges provided with surface portions conforming generally with the curvature of said arcuately bent portions and seated thereon, said lformed periphery of said diaphragm having a web portion extending between said mating edge portions, and a clamping ring having opposed jaw portions engaging the external surfaces oi' said arcuately bent portions for urging the same toward each other and clamplngly compressing said web therebetween.

8. A iluid pressure accumulator including cornplementary substantially identical, semi-spherihaving spaced outwardly extending mating edge portions comprising arcuately bent portions of said sheet metal, a rubber diaphragm having oppomtely extending iianges provided with a thickened formed periphery adjacent said bent edge portions, said iormed periphery having surface portio'ns conforming generally with the curvature oi' said arcuately bent portions and seated thereo said formed pelphery of said diaphragm having dicte said flanges extending said mating edges, a wire located outwardly with respect to said web and pontively limiting approaching movement of the outermost parts of said mating edges, and a clamping band surrounding said mating edges having relativelyfmovable 'jaw portions the arcuately'bent portions-ofthe latter at a location inoutwardly therefrom l spaced outwardly extending wardly of said wire ring and comprising means V for urging said jaw portions toward each other in order to urge said arcuately bent and adjacentparts of said mating edges toward Aeach other into clamping relationship with respect to said web while the outer extremities oi said mating edges are held against inward deection by said wire ring.

9. In a iluid pressure accumulator having complementary sheet metal sections including spaced outwardly extending mating edges and an elastic diaphragm for partitioning the interior of said accumulator, one of said sheet metal sections having an aperture therein and a surrolmding outwardly extending ange comprising sheet metal portions oi' said section; la iitting detachably securable to said section having externally threaded tubular portion extending through said aperture and a head portion provided with a recess for receiving said flange, said recess having a constricted inner extremity for wedgingly urging said flange against said tubular portion, a nut member threaded on the internal end of said tubular member for bearing against the internal side of said tubular member and urging said ilange into said recess and means connected to said fitting for communicative connection with the interior of said accumulator. f

10. In a iluid pressure accumulator having complementary sheet metal sections including tachably securable to said section having an ex- 1 ternally threaded tubular portion extending through said aperture and a head portion providedV with a recess for receiving said ilange, said recess having a ity for wedgingly urging said flange against said tubular portion, a nut member threaded on the internal end of said tubular member for bearing against the internal side of said tubular member and urging said flange into said recess, a shield mounted on said nut for protecting said diaphragm from injury and means connected to said fitting for communicative connection with the interior o f said accumulator.

11.l In a huid pressure accumulatorv having complementary sheetmetal sections including mating edges and an elastic diaphragm for partitioning'the inte'- rior of said accumulator, one of said sheet metal sections-having an aperture therein and a surrounding outwardly extending iiange comprising sheet metal portions of said section; a ntting detachably securable to said section having an` tubular portion extending of said section surrounding said tubular portion and engaging the junction of said` section and said ange, a nut member threaded on the internalside of said ing said yieldable sealing element, said nut member having an abutment en'gageable with the internal side of said sheet metal section for urging said flange' into said recess and means vconnected to said fitting .for communicative connection with the interior of said accumulator.

- 12. A iiuid pressure accumulator comprising constricted inner extremaperture and a head portion protubular member for compressmating edge portions, ediaphram comprising comnlementars sheet`v metal fins main wollV portions end outwardly exten y resilient material for partitioning the interior of seid accumulator and including relatively "chick marginal poi-tions, said margins!l portions hav'- .ing an enter port extending between pei-ts of said mating edge portions for providing e seal therebetween and en inner part disposed within the space confined-by saidxnein wel! portions,

e metal wire embedded in seid inner part of of said meting edge portions.

seid 'f portion adjacent seid mating edge Y.portions for opposing inward expansion of the istering with seid cuter' part of seis marginal portion for compressing the latter between parts GEORGE J. NER', JB. y

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